ASTM D4198-82(1998)

Standard Test Methods for Evaluating Absorbent Pads Used with Membrane Filters for Bacteriological Analysis and Growth

SCOPE
1.1 These test methods cover the determination of the nutrient-holding capacity and the toxic or nutritive effect on bacterial growth of organisms retained on a membrane filter, when the absorbent pad being tested is used as a nutrient reservoir and medium supply source for the retained bacteria.  
1.2 The tests described are conducted on 47-mm diameter disks, although other size disks may be employed for bacterial culture techniques.  
1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Dec-1998
• ICS: 07.100.10 - Medical microbiology
• Technical Committee: D19 - Water
• Drafting Committee: D19.08 - Membranes and Ion Exchange Materials

Relations

• Replaced By: ASTM D4198-82(2003) - Standard Test Methods for Evaluating Absorbent Pads Used with Membrane Filters for Bacteriological Analysis and Growth
• Effective Date: 29-Oct-1982

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 4198 – 82 (Reapproved 1998)
Standard Test Methods for
Evaluating Absorbent Pads Used with Membrane Filters for
Bacteriological Analysis and Growth
This standard is issued under the fixed designation D 4198; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope pared to cultures grown on spread plates and to membrane
filters placed directly on agar with no absorbent pad.
1.1 These test methods cover the determination of the
nutrient-holding capacity and the toxic or nutritive effect on
5. Significance and Use
bacterial growth of organisms retained on a membrane filter,
5.1 These test methods are appropriate for qualifying absor-
when the absorbent pad being tested is used as a nutrient
bent pads used with membrane filters for bacteriological
reservoir and medium supply source for the retained bacteria.
enumeration.
1.2 The tests described are conducted on 47-mm diameter
5.1.1 The test methods described are applicable to quality
disks, although other size disks may be employed for bacterial
control testing of absorbent pads by the suppliers and users of
culture techniques.
these pads and to specification testing of absorbent pads
1.3 This standard does not purport to address all of the
intended for use with membrane filters in bacteriological
safety concerns, if any, associated with its use. It is the
enumeration.
responsibility of the user of this standard to establish appro-
5.2 Other pure culture organisms and their appropriate
priate safety and health practices and determine the applica-
culture medium may be substituted for the E. coli and M-FC
bility of regulatory limitations prior to use.
media for specification testing, as required.
2. Referenced Documents
6. Apparatus
2.1 ASTM Standards:
2 6.1 Filtration Units for membrane filters with side-arm
D 1129 Terminology Relating to Water
flask and tubing.
D 1193 Specification for Reagent Water
6.2 Vacuum Source.
D 3508 Method for Evaluating Water Testing Membrane
3 6.3 Vortex Mixer or similar mixer.
Filters for Fecal Coliform Recovery
6.4 Forceps, flat-bladed.
3. Terminology 6.5 Incubator capable of maintaining temperatures of 44.5
6 0.2°C.
3.1 Definitions—For definitions of terms used in these test
6.6 Stereoscopic Microscope and Illuminator.
methods, refer to Terminology D 1129.
6.7 Illuminated Magnifying Stand for counting colonies on
4. Summary of Test Methods agar spread plates.
6.8 Hand Tally Counter.
4.1 Test Method A involves saturating a 47-mm absorbent
6.9 Autoclave.
pad with water and determining the volume of water held by
6.10 Analytical Balance readable to the nearest 1 mg.
the pad by weighing the pad dry and when fully saturated.
6.11 Petri Dish, 50-mm, nonsterile.
4.2 Test Method B involves culturing micro-organisms from
6.12 Expendable Equipment:
suspensions of pure cultures on a 0.45-μm membrane filter,
6.12.1 Filters (gridded, 0.45-μm, 47-mm) sterile, for water
which is placed on the test absorbent pad saturated with the
testing.
appropriate growth medium. The resultant cultures are com-
6.12.2 Absorbent pads (47-mm), sterile for the growth test.
6.12.3 Petri dishes, sterile 50-mm and 100-mm.
6.12.4 Pipets, sterile, 10-mL, 0.1 mL graduations, accuracy
These methods are under the jurisdiction of ASTM Committee D-19 on Water
and are the direct responsibilities of Subcommittee D19.08 on Membranes and Ion
of 6 5%.
Exchange Materials.
6.12.5 Test tubes, sterile, 20-mL, with screw caps.
Current edition approved Oct. 29, 1982. Published March 1983.
2 6.12.6 Bent glass rod, sterile, for spreading bacterial cul-
Annual Book of ASTM Standards, Vol 11.01.
Discontinued; see 1994 Annual Book of ASTM Standards, Vol 11.02. tures.
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NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 4198 – 82 (1998)
6.12.7 Burner, for flame sterilization. 11.1.4 After the pads are fully saturated (20 to 30 s), pour
off the excess water and shake out any remaining excess.
7. Reagents and Materials
11.1.5 Cover the dishes and weigh again.
7.1 Purity of Water—Unless otherwise indicated, reference
11.2 Method B—Culture Technique:
to water shall be understood to mean reagent water conforming 11.2.1 Prepare a set of ten 100-mm sterile petri dishes with
to Specification D 1193, Type II, with 0.2-μm membrane
16 6 1 mL of M-FC agar. Make sure the agar plates are at
filtration. In addition, suitability tests for determining the room temperature and that the surfaces are dry before using.
bactericidal properties of the reagent grade water should be
11.2.2 Prepare a set of five 50-mm sterile petri dishes with
performed. the sterile pads. To each pad add 1.8 mL of sterile M-FC broth
7.2 M-FC Agar with Rosolic Acid—Fecal coliform medium
and pour off the excess.
specific for the membrane filter technique. 11.2.3 Test five replicate sets of three aliquots. Each repli-
7.3 M-FC Broth with Rosolic Acid—Broth nutrient for
cate shall include (a) two membrane-filtered samples (one on
bacterial growth. agar, one on a pad), and (b) one spread plate.
7.4 Peptone Water, 0.1 %.
11.2.4 Add 0.1 mL of the diluted culture solution from 10.7
7.5 E. coli (ATCC 11229). to the agar plate from 11.2.1 and using a sterile bent glass rod,
spread over the surface of the agar. Cover the plate.
8. Preparation of Equipment and Materials
11.2.5 Set up two sterile filter funnels with flasks so that the
8.1 Washing and Cl
...